fix: address daily paper review feedback

plugins/daily_paper/README.md

@@ -1,6 +1,6 @@
 # Daily Paper Plugin
 
-[中文](README_ZH.md)
+[中文](https://github.com/agentscope-ai/ReMe/blob/main/plugins/daily_paper/README_ZH.md)
 
 Daily Paper selects three papers from the Hugging Face Papers weekly and monthly rankings, downloads their arXiv PDFs,
 and produces detailed Chinese reading notes plus a roughly five-minute Chinese brief. This directory is an independent

plugins/daily_paper/src/reme_daily_paper/base.py

@@ -83,7 +83,7 @@ def now(timezone: str | None = None) -> dt.datetime:
         return dt.datetime.now()
     try:
         return dt.datetime.now(zoneinfo.ZoneInfo(timezone))
-    except (KeyError, zoneinfo.ZoneInfoNotFoundError):
+    except (KeyError, ValueError, zoneinfo.ZoneInfoNotFoundError):
         return dt.datetime.now()
 
 

plugins/daily_paper/tests/test_daily_paper.py

@@ -30,6 +30,7 @@ from reme_daily_paper import arxiv as arxiv_utils
 from reme_daily_paper import huggingface_papers as hf_utils
 from reme_daily_paper.base import (
     normalize_chinese_title,
+    now,
     replace_surrogates,
     write_atomic,
     write_markdown,
@@ -95,6 +96,12 @@ def test_daily_paper_replaces_surrogates_in_text_and_titles():
     assert normalize_chinese_title("论文\ud800标题", "fallback") == "论文\ufffd标题"
 
 
+@pytest.mark.parametrize("timezone", ["/etc/localtime", "../UTC", "invalid\x00timezone"])
+def test_daily_paper_invalid_timezone_falls_back_to_local_time(timezone: str):
+    """Invalid IANA timezone keys retain the workflow's local-time fallback."""
+    assert now(timezone).tzinfo is None
+
+
 @pytest.mark.asyncio
 async def test_daily_paper_atomic_write_replaces_surrogates(tmp_path: Path):
     """Markdown writes always produce valid UTF-8 even when model output is malformed."""